Canopy switch



`April 3o, 1929. D, M E FEVER '1,711,417

lCANON swITcH Filed Feb. 15, l192e gli mmm IW] a5 f /7 .if

f E f5 E.; 27 f/ Yllll.'llllllllllllllllll`- attenua? 'Patented Apr. 30, 1929.

`UNITED STATES PATENT OFFICE.

DANIEL M. LE FEVER, F SOLVAY STATION, NEW YORK, ASSIGNOR TO PASS & SEY- MOUR, IN C., OF SOLVAY, NEW YORK, A CORPORATION 0F NEW YORK.

CANOPY SWITCH.

Application filed February This invention relates to electrical switches and more particularly to those known as canopy switches.

It is a general object of the present invention to provide a novel and improved form of canopy switch.

More particularly it is an object of this invention to provide a canopy switch of t-hc thin type including novel features such as the method of retaining the cont-acts in position. the method of bringing the lead wires out from the switch and the method of providing a one-way operating knob.

Another object of the present invention consists in the provision of a canopy switch having an insulating base provided with contact receiving recesses, together with a cover for said base which provides the solo means for retaining the contacts in position.

Still another object of the present invention consists in the provision of a canopy switch having parallel conductors protruding from one side thereof, said conductors being directly connected to the stationary contacts and assisting in retaining them in position.

A further object of the present invention consists in the provision of what may be termed a one-way or ratcheting operating knob, means being provided to prevent the mob from becoming completely separated from the switch and thus lost. v

In the accompanying drawing and following specification there is disclosed by way of example onlyl a single embodiment of the present invention, it being understood, however, that various changes may be made therein by those skilled in the art without departing from the spirit of the inventionC or the scope of the attached claims.

In said drawings:

Figure 1 is a plan view of the completed switch;

Figure 2 is a similar view' with the cover removed and the operating stud shown in section; l

Figure 3 is a longitudinal verticalv section thru the switch showing the same mounted in position in a canopy;

Figure 4 is a transverse vertical section on line 4-4 of Figure 2: and

Figure 5 is a perspective view of one of the stationary contacts and its associated conductor. A

55 Like figures of reference refer to sirnilar ed operating v15, 1926. Serial N'o. 88,453.

parts throughout the various views and the description.

Canopy switches are generally manufactured in two styles, first, those which are usually small and cylindrical but of considerable longitudinal thickness; e and second, tliosewhich are thin and flat having but little longitudinal thickness and greater' extent transversely. The switch of the present construction is of the latter type and is intended for use in thin fiat canopies such as shownat 10 in Figure 3 where the space between the top of the canopy and the wall or other surface upon which the same is mounted is materially limited, as in candle and like tixtures.

Referringr to the closed at 11 the base,

drawings, there is disor main portion, of the switch formed of any suitable insulating material such as porcelain, fiber, or the like. It is shown as substantially rectangular in form altho the exact shape is a matter of choice.

It is provided with a Hat bottom 12. The upper or top face of the insulating block is provided with a shallow recess 13 havingv its bottom parallel to the bottom 12 of the insulating block and being bordered or outlined by the peripheral flange or rib 14. Near the center of the recess 13 there is provided a second recess 15 substantially circular in general outline and extending considerably more than half way thru the block. The bottom 16` of this recess is substantially flat and parallel to the bottom 12 of the block` while the side walls of the recess are at right angles to the bottom thereof. These walls 17 are shaped to provide the four ratchet notches 18 and 19 having the stop faces 20 and 21 respectively.

The recess 15 is adapted to receive the movable contact spring 22, best shown in Figure 2. This spring, formed of a good conducting metal is made suiciently resilient for the requirements of switch. It is formed from a thin strip of such metal having a width slightly 4,less than the distance between the bottom wall 16 of the recess 15 and the bottom of the recess 13. Its central portion 23 is straight and is adapted to be received in the transverse longitudinal slot 24 Yin the insulatstud 25, which will be further described later. This portion 23 closely cngages the walls of the slot and the whole strip is of such a lengt-h as to allow its curved ends 26 to be bent away from the center at substantially right angles.n After these right angled bends 27 the portions 26 of the contact are bent into arcuate form sotl1at the tips of the same lie substantially over and parallel to the center Iportion as best shown in Figure 2 and are adapted to have spring pressed engagement with thc walls 17 of the recess 15. It will be seen that this construction allows clockwise rotation of the contact spring, as viewed in Figure 2, in substantially 90 arcs but reverse movement is prevented by the ends of the spring engaging with the stop walls or 21. It will further be seen that clockwise rotation of the spring effected by turning the stud must be made in these 90 steps for the angles of the ratchet walls are such as to cause retrograde motion of the spring unless it is stopped with the ends thereof against the stop walls. It will further be seen that as leave the walls 18 or 19 when moving in a clockwise direction they will suddenly snap down along the walls 20 or 21 to give the characteristic snap action to the switch on both the make and break. 0

The full length of each of the walls 19 is adapted to be covered by the arcuate portion 28 of one of the .stationary contacts 28. When the rotatable spring contact is in the position shown inv Figure 2 with its ends engaging the walls 18, the contacts 28 are iso ated from each other, but, when the operating stud 25 is rotated thru a 90 angle from the position shown in Figure 2, the contact spring assumes the dotted line position and the tips 26 thereof are pressed into engagement with the stationary contacts 28 to thus bridge them and complete the circuit to which they are connected.

The construction of the stationary contacts 28'is best disclosed in Figure 5 where it will be seen that'they are formed from a single .piece of sheet metal pressed or stamped into form. The arcuate portion 28 has projecting at right angles and from its top edge, substantially at the center thereof, the tab 29 which is provided with the downwardly struck U-shaped wire receiving channel 30 transversely thereof. As shown in Figure 5 it will be seen that a conductor wire 31 has its insulation removed for a short distance at onev end s'o that the bare conductor 32 can` be placed in the channel 30 and soldered in position as showfn, thus forminga positive electrical and mechanical connection between the terminal wire and the stationary contact. Each stationary contact and its associated terminal wire is mounted in position in the block 11'so that the portion 28 lies with its convex* side abutting a wall 19 of the recess 15. The tab 29 is received in a notch'or channel 33 so that its upper surface is flush with the bottom wall of the recess 13. Connecting the notch 33 is a deeper one 34 shown in Figures 3 and 4 to receive the channeled porthe ends of the springs in position in the switch block in the same manner but they are provided with terminal conductors 31 projecting from opposite sides thereof so that the two conductors 31 project from the same edge of tlie'switch, being received in parallel channels 35 in the switch block which are of such a depth as to allow the insulation on the wires to project but slightly above the bottom of the recess 13. These channels 35 extend to the edge of the block and at their opposite ends are connected directly withthe recesses 34. In assembling the switch the contacts are dropped into the osition shown in Figure 2 and a sheetof insu ating material having a. thickness equivalent to the height of the walls 14 is fitted into the recess 13 with its edges closely engaging the inner faces of the walls 14. This insulating sheet 36 is perforated as at- 37 to allow the operating stud 25 to freely pass thru the same. It is retained in lposit-ion by means of the metalcover 13 which is of the same size as the insulating block and is secured thereto by the hollow rivets or fastening means 38 having one end recessed in the block asat 39, and suitably covered 1f desired, and the other end projecting thru suitable apertures in the insulating sheetand cover 13. The rivets are then swaged or spun over to securely hold the cover 1n position.`

This cover presses the insulation sheet 36 tightly against the. tops of the tabs 29 and the upper edges of the arcuate portions 28 of the contacts and also against the slightly projectinv portions of the insulation on the wires 31 and thus securely clamps the contacts 1n position, this being the sole means of so retaining them. It will be noticed that each contact is prevented from moving radially inwardly by the en agement of its channel 30 with* the inner Wal of its recess 34 and is prevented from moving tangentially by the engagement of the edges of4 the tab 29 with the walls of its recess 33.

Thecover 13 is pressed upwardly above the recess 15 as shown at 40 and has secured thereto the bushing 41 which passes thru an aperture in the part and is swagedover as shown at 42 to retain the same in posltion. The bushing 41 is adapted to be passed thru a suit-able aperture in the canopy10, and to receive, on its external threads, the knurled nut 43 which engages the outer face of the canopy and securely fastens the switch 1n position therein.

The bushing 41 is provided with the cylindrical bore 44 which is reduced in diameter at 45 to form the squareshoulder 46 near the top thereof. These two bores are adapted to receive the operating'stud-25, the lower ortion of which, as prevlously pointed out, 1s formed of insulating material and slotted other suitable same.

to receive the spring contact member. This lnsulatmg portionis provided at its upper end with a reduced end 47 adapted to be re- 'Ceivcd in the bore in the metallic portion 48 into which it is secured by swagin punching, or in some similar manner. he lower portion of the metal part of the stud is of the same diameter as the portion 25 and is journaled in the bore 44 in the bushing 41. It is provided with a reduced upper end 49 which passes thru the smaller opening 45'in the bushing and extends above the same. rlhe smaller portion 49 of the stud is internally threaded as at 50, the thread being provided with a positive stop at the bottom.

An operatinghandle or knob 51 is adapted to be secured to the stud for the purpose of rotating the same. lt is provided on its outer surface with suitable knurling to assist in grasping it and is so attached to the stud that clockwise motion may be imparted to the However, upon attempted counterclockwise rotation of the knob the spring ends 26 come against the stop walls 2() or 21 and the knob is released from the stud and yet cannot be completely removed from the same, vas is customary with the usual operating knobs for canopy switches, which areV threaded onto a projecting stud on the operating stud. The operating knob 51 is bored at its bottom to loosely fit over the reduced end of the operating stud as shown at 51 and at its upper end is provided with the bore 52 of such a depth greater than the thickness of the fillister head of the screw 53. This screw has its lower end threaded to be received in the bore 50 in the metal portion of the operating stud and, when assembled, is tightly screwed against the positive stop at th'e bottom thereofL aThe upper end of the shank of the screw is, as shown at 54, smooth and of a smaller diameter than the base of the threads thereon. The partition wall in the operating knob between the bores 51 and 52 is threaded internally to engage with the threads on thescrew 53.

The relation of the parts is such that upon clockwise rotation o4 the operating knob the threads in the parts 55 engage the threaded portion of the shank of the screw 53 which projects above the part received in the operating stud and the bottom or" this partition 55 then engages the top of the reduced end 49 of the operating stud and thus the two are securely connected together so that the switch can be operated. However, upon an attemptn.' ed counter-clockwise rotation of the operating knob, the stud is prevented from being rotated by the engagement of the' spring ends 26 with either of` the stop walls 20 or 21, and the threads in the partition 55 are unserewed from the screw 53 and move up alongside of the unthreaded portion 54 of the shank oit' this screw so that continued counter-clockwise rotation of the knob will have no eect on the operating stud from which the knob will be completely disconnected. It is, however, prevented `from falling off by the engagement of the partition wall 55 with the under side of the fillisterthead of the screw. In this condition it assumes the position shown in dotted lines in Figure 3. It will thus be seen that a one-way or ratcheting knob is provided which, however, cannot be separated from the operating stud and lost. The threads on the inside of the nut 43 are of such a size as to pass over the operating knob which, therefore, need never be removed after once assembled even when mounting the switch in the canopy. i

Longitudinal movement of the operating stud in a downward direction is prevented by its engagement with the bottom wall 16 of the recess 15 and corresponding movement in an upwardY direction is prevented by the engagement of the larger portion of the stud with the shoulder 45 at the junction between the two bores in the supporting bushing. rll`he movable spring contact 22 is retained in position between the bottom wall 16 and the under surface of the insulating sheet 36 and it will thus be seen that this sheet performs the function of retaining not only the stationary contacts but the movable contact in position.

The simple manner of mounting the stationary contacts materially reduces the cost ot production of the switches and as previously described the assembling operation is extremely simple and no additional parts are required to retain the contacts in position.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a canopy switch, in combination, an insulating base having a recess" in one face thereof, said recess having a wall at right angles to said face, a contact having a portion thereof against said wall, another portion of said contact being parallel to said face, insulating means secured over said face to hold said Contact in position and a rotatable spring adapted to engage said contact.

2. In a switch of the class described, in combination, an insulating base having a lat face and a main recess opening on said tace, the periphery of said recess being formed with ratchet teeth, a pairpt similar opposed contact members each having a portion thereof lying against a tooth of said main recess, a portion of each contact being received in a separate subsidiary recess in said base, said base having a channel for each subsidiary recess connecting said recesses to the same edge of the base, and a conductor in each channel secured to the respective contacts.

3. A. contact for switches including in combination, a cylindrical segment, a tab 4. A' contact for switches including in combination, an arcuate portion, a tab projecting radially from an arcuate edge thereof, and a channel in said tab substantially parallel to a tangent to said arc at the junction of the tab therewith.

5. In a switch, in combination, a stationary contact, a movable contact, a studjcarrying said movable contact and mounted for rotation, an operating knob for said stud, a screw passing thru said knob and engaged in said stud, a threaded portion in said knob adapted to engage the threads of said screw and connect said knob and stud upon clockwise rotation of said knob.

6. In a switch, in combination, a stationary contact, a movable contact, a Ystud carrying said movable contact and mounted for rotation, an operating knob for said stud, a par# tition wall in said knob having a threaded opening therein, a screw passing thru said partition and secured in said stud, the threads said knob having a bore at the other end, a partition wall between said bores -having a threaded opening therein, a screw secured in said stud, ahead thereon adapted to lit in the bore in said knob to prevent its removal,

-threads on said screw projecting 'above said tion, an operating knob for said stud, having a bore at one end adapted to fit over said stud, said knob having a'bore at the other end, a partition wall between said bores having a threaded opening therein,- a screw secured in said stud, a head thereon adapted to fit in the bore in said knob to prevent its removal, threads on said screw projecting above said stud and adapted to be engaged by the threads .in said partition upon clockwise r0- tation of said knob to rotate the stud, a portion of the shank of said screw being smooth whereby upon counterclockwise rotation of said xknob the threads therein will pass freely over said portion so that reverse movement cannot be transmitted to said stud.

In testimony whereof I hereunto aiiix my signature.

DANIEL M. LE FEVER. 

